According Wikipedia Android rooting is no problem outside US.
And if I read it correctly, it is no problem in the US for cell phones
that are not bound to a provider like my prepaid free of contract cell phone.

Programming

I created my first "Hello world" application following these instructions.
No big development environment, just learn each step needed.

While the above was a Java program, I created an Android version of "tidy"
command line utility with free CodeSourcery C/C++ cross compiler for ARM.
Based on "tidy4aug00.tgz" I just had to change two Makefile lines:

Important is the "-static" change -- by that no libraries have to be installed on Android.
Here is "Android tidy" in action: